The urban area in many cities around the world is frequently intricate with various types of utilities beneath public roads. In contrast, there lacks a clear picture of the spatial positions of such utilities. The large quantities of utilities and the lack of quality as-built records make it a big challenge for both governmental authorities and utility undertakings to effectively manage and operate utility as well as road services. Ineffective management often leads to ineffective utilization of underground space, unnecessary and frequent road excavations, additional time and costs, poor logistics management and work organizations, damage to buried utilities, service disruptions, repair costs, and accidents of injuries and deaths.

This study investigates some key issues in manag...[ Read more ]

The urban area in many cities around the world is frequently intricate with various types of utilities beneath public roads. In contrast, there lacks a clear picture of the spatial positions of such utilities. The large quantities of utilities and the lack of quality as-built records make it a big challenge for both governmental authorities and utility undertakings to effectively manage and operate utility as well as road services. Ineffective management often leads to ineffective utilization of underground space, unnecessary and frequent road excavations, additional time and costs, poor logistics management and work organizations, damage to buried utilities, service disruptions, repair costs, and accidents of injuries and deaths.

This study investigates some key issues in managing space occupation by underground utilities, including a knowledge mining process of worldwide management practices, the establishment of an underground utility occupation index (UUOI) for measuring underground space utilization, the development of a prototype of a joint utility management system (JUMS), an investigation of the factors influencing utility undertakings’ behavioral intention in using a utility management system, and the examination of the causes of poor as-built records, the benefits of maintaining quality as-built records and the barriers and solutions to achieve quality as-built records.

Frist, a comprehensive literature review on laws, regulations and practices related to underground utilities management has been conducted, covering legislative frameworks, standard procedures, control methods, and best practices in cities around the world. A comparative analysis of these cities has been carried out, with an aim to draw experience and learn lessons for future improvements toward efficient management of underground utilities.

Second, UUOI is proposed as an indicator for measuring underground space in urban development. It can furnish detailed information such as existing utilities, underground space already occupied, and space available for future utilization by analyzing from multiple perspectives: utility, zone, road category, footway and carriageway, and district. UUOI provides the necessary precision of utilities and space information required by utility undertakings in the installation, operation, and management of underground utilities and consolidates from a small scale to a large scale to facilitate city governments in urban planning and development. Underground space utilization information is a prerequisite for efficient and cost-effective implementation, no matter on a small scale in the practice of the utility industry or on a large scale in the urban planning and development of city governments. UUOI supports governmental authorities and utility undertakings in their decision-making at both micro-level and macro-level. From the perspective of utility undertakings, UUOI of each road and each section thereof can be examined to obtain insights for routing new utilities. UUOI enables them to share information in making long-term and short-term development plans to avoid conflicts between utilities belonging to different companies and adopt suitable methods to minimize damage to existing utilities in construction, operation, and maintenance. From the perspective of governmental authorities, UUOI enables the differentiation and prioritization of areas of different levels of utility density and facilitates them in formulating guidelines for future urban development, establishing strategical development areas and issuing permits for road excavation works. The improved practices of both government authorities and utility undertakings will reduce disturbance to the public.

Third, a prototype of joint utility management system (JUMS) is developed, with improved workflow that integrates three processes: plan assessment process, excavation process, and completion process. The analytical functions for the three processes are web-enabled. JUMS meets the compelling need of underground space utilization by incorporating procedures of feasibility-check before excavation and uploading as-built information after completion of work. It can conduct necessary analysis of submitted utility alignment plans and prohibit infeasible utility alignment plan early before entering the public roads, thereby reducing unnecessary road excavations and minimizing disturbance to the public. The trial results have proved the usefulness of JUMS and the methodology in excluding unworkable plans, finding viable routes for new alignments of utilities, cataloging buried utilities, and facilitating authorities to manage underground space occupation systematically.

Fourth, to ensure successful implementation of a utility management system, an investigation is conducted on factors influencing utility undertakings’ behavioral intention. Venkatesh and Davis’ technology acceptance model is applied considering four external variables—information quality, system quality, compatibility, and technical support. A structured questionnaire survey has been conducted to collect necessary sample data and the SEM method is adopted to analyze the data. Nine hypotheses are constructed based on the technology acceptance model and other techniques and all are successfully validated according to the analysis of a questionnaire survey. The results suggest that information quality, system quality, compatibility, and technical support can indirectly affect utility undertakings’ behavioral intention to use a utility management system via influencing perceived ease-of-use and perceived usefulness. The results have confirmed that perceived usefulness and perceived ease-of-use are significant indicators for predicting utility undertakings’ behavioral intention, information quality has the largest effect on utility undertakings’ perceived usefulness of a utility management system, and system quality influences the perceived ease-of-use.

Fifth, as-built records of underground utilities are often inaccurate and unreliable so that the word “as-built” somehow loses its meaning. Poor as-built records also affect the performance and profitability of utility undertakings whose financial success depends on their ability to place facilities and provide services to customers in a timely and cost-effective way, which to some extent depends on the availability of accurate as-built records. It is important to create and maintain a reliable database of underground utilities, in which as-built records are a critical element. Through literature review, case studies, interview with experts and practitioners, and questionnaire survey, this study has investigated the benefits, causes, barriers and solutions to poor as-built records with an aim to shed some insight on the joint efforts of government and industry in establishing appropriate policies and strategies and workable code of practice to efficiently enhance the quality of as-built records. Specifically, this study has identified and validated 7 major benefits of maintaining quality as-built records, 6 major causes of poor quality as-built records, 6 major barriers to quality as-built records, and 9 solutions towards quality as-built records.

The SEM technique has been explored to evaluate the causal relationships of the latent variables (benefit, cause, barrier, and solution) and the corresponding observed variables that measure individual latent variables. Statistical analysis and various tests have been performed to the survey responses, including individual item reliability analysis, convergent validity analysis, significance analysis, one-sample Kolmogorov-Smirnov test, Monte Carlo simulation, Mann-Whitney U test, and Kruskal-Wallis H test. The analytical results indicate that the benefits, causes, and barriers listed in the above are statistically significant or very significant and the solutions are statistically useful or very useful. The item reliability and convergent validity are all at a satisfactory level, and in general there is no statistically significant difference between owners, contractors and consultants in the rating of most of the observed variables that measure the individual latent variables of benefit, cause, barrier and solution.

Outputs of this study would shed useful insights on what appropriate policies can be established on the side of the government and what workable codes of practice can be implanted on the side of utility industry such that the quality of as-built records can be efficiently improved by the joint efforts of government and industry. Accurate as-built information will play an irreplaceable role in urban planning, project design and construction, utilities operation and management, and ensuring order and efficiency in underground space utilization.